Study of a low molecular weight urinary protein - post-gamma globulin (p-gamma) continued. Animal model was established (dog) and the catabolism and metabolism of this protein explored. High levels of this protein were found in the brain, salivary glands and kidney. Radioimmunoassay of this protein was set up with our hybridoma antibodies and levels established in normal and pathological biological fluids. High levels are found in cerebrospinal fluid. Characterization of "leukemia" antigens with our monoclonal antibodies continues. Three putative turkey beta 2m "proteins" were isolated and partially sequenced. One of them has a possible amino acid sequence of human beta 2m. Studies with antibodies against this protein are aiding our efforts to establish the role of beta 2m in embryology.